Why Eating When You're Depressed Makes You Eat More

In Austin Powers, Fat Bastard explains that he eats when he's depressed, and he's depressed because he eats. Turns out, these kinds of vicious circles of eating are due to a drug-like hit-and-comedown response in your brain, activated specifically by rich foods.

A team of researchers, from Montreal Hospital Research Centre, has been studying brain activity during bouts of repeatedly eating fattening foods. Stephanie Fulton, one of the researchers, explained to EurekAlert:

"In addition to causing obesity, rich foods can actually cause chemical reactions in the brain in a similar way to illicit drugs, ultimately leading to depression as the 'come-downs' take their toll. We are demonstrating for the first time that the chronic consumption of palatable, high-fat diets has pro-depressive effects."

To get to the bottom of things, the team conducted some experiments on mice, and monitored how different diets affected the way the animals behaved. They used existing techniques to evaluate the relationships between food and resulting behaviour, and later analysed their brains to identify real, physical changes.

What they found, which is published in the Journal of Visualized Experiments, is interesting. After deprivation from their respective food stuffs, mice fed higher-fat diets got more anxious and—in so much as a mouse can be—depressed. They were withdrawn, shied away from open spaces, and made little effort to escape when trapped.

What's more, their brains were physically altered by the experience. They produced more CREB—a molecule that affects memory formation—and exhibited higher levels of corticosterone, a hormone that is associated with stress.

Since mice and humans share the same dopamine-based reward system, this finding suggests that binging on rich, high-calorie foods causes real, measurable changes in behaviour which only become apparent once food is withdrawn. The obvious—and disastrous—solution, of course, is to carry on eating.